Abstract: In order to establish the aircraft engine startup model used in a flight simulator,the modeling and simulation methods for turbofan engine startup were studied,the basic rules for establishing the startup model were developed.Accordingly,the main performance models which dominate the dynamic performance of engine startup in normal working condition were developed based on component modeling method,while the typical malfunction models were developed using the designed malfunction factor,so the normal engine startup procedure and malfunction simulation in the starting process were carried out.The comparisons between the simulation results in normal/fault conditions and test data indicate that,the normal startup model reflects the accelerating ability of every startup phase correctly,and the malfunction models represent the fault logic and effects,thus meeting the requirements of flight simulation.